Commercial laundries commonly use power driven rolls usually known as flatwork ironers. Frequently four or more power driven rolls are used in a single unit of equipment. These rolls are usually covered with asbestos fabric. Such fabric is commonly woven from yarns which are called asbestos yarns although they generally contain a small proportion of staple fiber other than asbestos for the purpose of holding the asbestos fibers in position.
It has heretofore been proposed to treat the asbestos fabric of ironer roll covers with a material to make the work-contacting surface smooth, durable, tough, tear-resistant and wear-resistant. For example U.S. Pat. No. 2,534,818 issued to Holroyd et al. shows the provision of a liner or padding wound around the roll prior to applying an asbestos cover prepared by passing woven asbestos fabric through an aqueous impregnating bath containing a thermosetting resin, such as a melamine-formaldehyde resin, in solution in water together with a thermoplastic resin, such as polymerized methyl methacrylate, and wax in emulsion, drying, calendering and curing whereby the intermingled resins and wax give the fabric a smooth porous surface, good wear-resisting properties and good tear-resisting properties.
Similarly, U.S. Pat. No. 2,033,894 to Crockford shows a flatwork ironer roll comprising a padding layer 6 which may supplement the usual padding or replace it altogether. Layer 6 is preferably made of woven asbestos fabric. Around layer 6 is disposed protective insulating layer 5 which likewise is made from woven asbestos fabric but is provided with resinous impregnation 10 which typically is a heat-hardened phenolic resin material. The cured resinous material imparts to the asbestos roll covering a smooth and indurated surface which does not materially impair the flexible properties of the fabric. Protective covering 5 is shown as a prolongation of the unimpregnated asbestos padding layer 6, the two layers being integrated by lines of stitching 8 which secure the lapped ends together.
U.S. Pat. No. 2,333,824 to Schoepf shows an ironer roll cover unit which comprises a multiply woven fabric pad section 11 adapted to be wrapped around the roll and a single ply inner fabric outer cover section woven with smaller weft threads than the weft threads in the pad section, the two sections being woven as a single unit with common warp thread extending continuously throughout the length of the unit. The weft threads of both sections preferably are asbestos threads and the warp threads likewise preferably are constituted by some form of asbestos thread.
None of the patents referred to in the foregoing teaches the present invention which resides in an ironer roll cover unit comprising a length of fabric having the same construction throughout so that no fabric seam is present, thereby eliminating unevenness and the necessity for seaming, and having a padding portion which constitutes a base layer on the roll and is free from resinous material or other solid material which would materially reduce the padding effectiveness of the padding portion. The roll cover unit of the present invention also embodies a portion which constitutes an outer work-contacting section which is based upon an integral portion of the fabric forming merely an extension of the fabric used in the padding portion. This work-contacting section is formed by impregnating the fabric constituting this portion with a thermosetting resinous material which provides the desired porosity, smoothness, heat resistance, wear resistance and other qualities required in the work-contacting portion of an ironer roll cover. The fabric used for both the padding portion and the work-contacting portion preferably is a woven fabric made with warp and weft yarns both of which contain enough heat-resisting fiber to give a high degree of heat resistance, both warp and weft desirably comprising predominantly or exclusively heat-resisting fibers.